1.今天 當我  執行  git add  somefile 的時候，出現 如下 錯誤：

If no other git process is currently running, this probably means a
git process crashed in this repository earlier. Make sure no other git
process is running and remove the file manually to continue.

解決方法：

rm -f ./.git/index.lock

2. 編譯ICS時 出現 如下錯誤：

build/core/java.mk:20: *** dalvik/dexgen: Invalid LOCAL_SDK_VERSION '4' Choices are: current .  Stop.

解決方法：

rm -rf prebuilt ; repo sync prebuilt